Ham Radio Homebrew Informations: Re: [HamBrewers] Re: Required- Noise reduction circuits for speaker

Monday, December 26, 2011

Re: [HamBrewers] Re: Required- Noise reduction circuits for speaker

Dear Rajesh,

Tks a lot and it does work!

73,

dev

http://hamrmipl.blogspot.com/

--- On Sun, 12/25/11, Nitin Muttin <vu3tyg@yahoo.co.in> wrote:

From: Nitin Muttin <vu3tyg@yahoo.co.in>
Subject: Re: [HamBrewers] Re: Required- Noise reduction circuits for speaker
To: "HamBrewers@yahoogroups.com" <HamBrewers@yahoogroups.com>
Date: Sunday, December 25, 2011, 1:39 PM

Hi Rajesh,

Thanks, currently suing the same on the external speaker and it helps to a certain extent.

73's

Nitin [VU3TYG]

From: Rajesh K <kc2kby@airtelmail.in>
To: HamBrewers@yahoogroups.com
Sent: Sunday, 25 December 2011 1:26 PM
Subject: RE: [HamBrewers] Re: Required- Noise reduction circuits for speaker [1 Attachment]

Nitin,

You could try this one also(A $1.00 Noise Reducing Speaker in the attached newsletter). I have homebrewed a speaker for my IC-718 and got some improvement.

73

Raj VU3RGK

From: HamBrewers@yahoogroups.com [mailto:HamBrewers@yahoogroups.com] On Behalf Of vu3tyg
Sent: Saturday, December 24, 2011 11:39 PM
To: HamBrewers@yahoogroups.com
Subject: [HamBrewers] Re: Required- Noise reduction circuits for speaker

Thanks Yan for the information, will try your suggestion

73's and HNY
Nitin [VU3TYG]

--- In HamBrewers@yahoogroups.com, "Yannick (XV4Y)" <yannick.devos@...> wrote:
>
> Hi Nitin,
>
> This circuit works great as Audio LP filter. I use it in my Bitx20 with great results.
> Filtering high frequencies spikes it also reduce the need for an AGC.
> http://lpistor.chez-alice.fr/filtrebf.htm
>
> Try to look for circuit using MAX293 or similar (MAX291 or 292 use Butterworh or Bessel, not elliptic filters), you will find a lot on internet.
> Some also includes an active HP filter built around an OP-Amp.
>
> Sometime this kind of filter is called SCAF.
>
> 73 and HNY,
> Yan.
> ---
> Yannick DEVOS - XV4Y
> http://xv4y.radioclub.asia/
> http://varc.radioclub.asia/
> http://www.qslwatch.com/
>
> Le 22 déc. 2011 à 23:19, Nitin Muttin a écrit :
>
> >
> >
> > Has anyone got any simple noise cancelling circuits either dsp or otherwise which would remove the high tones on ssb reception, this includes the background radio noise. I understand that there was an article in the QST November 2011 issue.
> >
> > 73's
> > Nitin [VU3TYG]
> >
> >
> >
>